Signaling system



l June 30, 1925.

J. C. FIELD SIGNALING SYSTEM Filed NOV, 26, 1920 2 Sheets-Sheet 1 dos June 3u, 1'925. 1,543,836

J. C. FIELD I SIGNALING SYSTEM Filed Nov. 26, 1920 2 Sheets-Shet 2 Patented .lime 30, 1925..

Param*t OFFICE.

JOSEFH C. FIELD, OF ORANGE, NEW JERSEY, ASSIGN'OR T0 WESTERN ELECTRIC COM- PANY, mconrona'rnn, oF NEWIORK,

N'. Y., A CORPORATION OF NEW YORK.

1 SIGNALING SYSTEM'.

y v Application led November 26, 1920. Serial No.` 426,409.

` To all whom t may concern:

Be it known that I, JOSEPH C. FIELD, a citizen' of the United States, residing at Orange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Signaling Systems,

of which the following is a full, clear, concise, and exact description.

This invention relates to signaling systems, and particularly to improvements in selective signaling systems for train despatching and like purposes wherein the necessary electrical energy` is supplied from a source located at a central' station.

The principal object of the present invention is the provision of a selective signaling system embodying means whereby the current generating device is entirely under the control `of the impulse transmitting mechay msm.

The second object of this invention is the provision of a rectilier in combination with .a system of train despatching, which wil.'

be rendered active only during the operation of the impulse transmitting mechanism.

The invention provides a selective slgnal- `ing system comprisinga number 'of waystations, at each of which is a selector selec-f tively responsive to va definite combination vor code of impulses. y The impulses for effecting the operation ofthe selectors are l supplied from a rectilier set under the con-y ."trolof a calling or impulse transmitting key. l x

The above and other objects of the invention will be more clearly understood after I considering the following .description when taken in conjunction with the accompanying drawingsLwherein Fig.`1 illustrates'a system embodying the principle of control- -ling thevapplication of a source of electrical energy to the 'line only during the interval the impulse transmitting mechanism is operated. Fig. 21illustrates-an alternative arrangement of the one disclosed in Fig.l 1, only so much of the system lbeing shown as is necessary for a clear understanding of the invention. Fig. 3 is ja modification of the arrangement disclosed in Fig. 1, wherein two vacuumtubes are connected in series.. Fig. 4 illustrates another embodiment ofthe invention being similar to the arrangement disclosed in Fig. 3; Fig. 5 illustrates a further embodiment of the invention in 'which two vacuum tubes are connected 11.1

multiple, while Fig. 6 shows two vacuum tubesof the twoelement type arranged to rectify both halves of the waves.

Referring especially to Fig. 1, there is shown a pair of conductors 4 and 5 extending from a central or train despatchers olice A to a plurality of way-stations B and` C. The apparatus to the left of the broken line 3 3 is located at the central or train despatchers office, and the portion to the right thereof is located at the various way-stations to which the conductors 4 and 5 extend. At each way-station there( is a selector 6, the

Aoperating windings of which are connected in bridge of the conductors 4 and 5, and 1n series with the retardation coils 7 and 8.r

Each way-station is equipped with the usual apparatus which for the sake of clearness i has been omitted. A selector suitable for use with this invention is disclosed in Patent No. 1,343,256 issued June 15, 1920, and since this patent illustrates and describesin detail the various operations of the selectorit is considered unnecessary to show a complete structure here. It is, of course, understood that the invention is not limited Ato the pro- Vision of such a selector. y

At the central or train dispatchersoice A,

minal ofthe plate electrode 13 of a vacuum tube rectifier 14. The vacuum tube rectifier 14 is also provided with a cathode, or heated filament-15 having one terminal thereof connected with the winding 12. Current for heating the filament to incandescenee so as to emit elctrons is thus supplied from the primary winding19 through the secondary winding 12. -Normally current is plied to the filament 15 as/the circuit thereof 1s normally open at the contactszof relay 16. This relay is controlled through contacts ontransmitters 17 and 18. A pole changing relay 19 is provided for reversing the connections from the vacuum tube rectifier 14 to the line conductors 4 and 5. ,Connected in parallel with relay 16 is a relay 20 which is likewise controlled by the transmitters 17 and 18. This relay 2() extends through its not apl contacts the conductors l4 and 5 to the contacts of the pole changing relay 19. The transmitter 17 is for calling way-station B and 18 for calling station C. Each of the 'transmitters is provided with teeth 21, "centain ones of which may be blockedout by one or two adjustable cams 22 and 23 to obtain a certain number and combination of effective teeth for calling purposes. The transmitters are each adaptedv to rotate in the direction of the arrow, and the teeth thereof control the engagement of contact springs 24 and 25. These contacts control the energization of pole changing relay 19. The free end of contactspring 24 is bent downward, andis adapted to complete the energizing circuit for relays 16 and 20.

The contact spring 24 of each transmitter is normally out of engagement with the revolvin disc thereof. During the revolution o the discof each transmitter, contact,

spring 24 is in engagement therewith, maintaining the circuit for relays 16 and 20 closed'to complete the circuit of the filament 15 of the vacuum tube rectifier 14 and the secondary winding 12, and the extension of conductors 4 and 5 to the contacts of pole changing relay 19 respectively. Assuming that transmitter 17`-is operated as the disc thereof starts to rotate, the circuit of `relays 16 and 20 is completed operating these relays. The closure-of 'the contacts of relay 1.6 connects the secondary winding 12-of the power transformer 10 with the cathode or ,heated filament 15. Since current is normally traversing the primary winding 9 filament 15 will receive suilicient energy to eiiectthe operation of the vacuum tube rectilier 14. Currentis thus caused to flow to the line conductors 4 and 5. upon the energization of relay 20. As contact spring 24 rides upon the first tooth, it also engages contact spring 25 to actuate the pole chang.`

ing relay 19 y current from battery 26 to reverse the' connections of the output circuit of the tube.14 to the line conductors 4 and 5. When contact spring 24 drops between two teeth, relay 19 will be deenergized, and during the time this contact is passing over cam 22, relay 19 will be energizedv to furnish a prolonged impulse of one polarity.- As the disc continues to rotate, current impulses are sent over the line conductorsI 4 and 5.

The selector at way-station B will respond operate to smooth out current impulses used for selectively signaling the way-stations to prevent disagreeable thumps in a receiver which may be in bridge of the conductors 4 and 5 durlng the periods of operation of the transmitter. A despatchers telephone set 35 comprising the usual transmitter and receiver isl associated lwith conductors 4 and 5. Connected in the output circuit o f the vacuum tube rectifier 14 is a condenser 36. By the use of a condenser connected in this manner the rectilied voltage is much higher and the wave shape with light loads is approximately the same as with a direct current battery.

In all of the other figures which illustrate 1g. 1 has beenfshown. It is of v 'Y provided, but having the lsecondary winding divided in two sections, one section being connected with the plate electrode 38, the other to the plate electrode 39. With such an arrangement both halves of the wave may be rectified. The filament circuit as before is controlled through the contacts of relay 16.

The modification illustratedv in Fig. 3 is similar to the one shown in Fig. 1, except that two vacuum tubes 40 and 41 of the two element type are employed. The vacuum tubes `40 and 41 are connected in series. Each of the tubes has its filament circuit conrespectively. The completion of the lilanected with secondary windings 42 and 43 ment circuit with the respective secondary winding is controlled through contacts on .relay 44. An arrangementA of the character disclosed in Fig. 3 not only rectifies half of the wave,vbut also permits the use' of vacuum tubes of a lower voltage.

Referring to Fig. 4 which illustrates an alternative arrangement of the one disclosed in Fig. 3, there is shownl a pair of vacuum tubes 4 5 and 46.l As in Fig. 3 the filaments of the tubes have an individual secondary winding which is associated' therewith upon the energization of relay 44. This arrangement, however, differs from the one disclosed in Fig. 3' in that the secondary winding of t-he power transformer is intwo sections. With the secondary winding of the power transformer divided in this manner a condenser is connected in each of the respective circuits. These condensers are designated by the numerals 47 and 48.

In Fig. 5 is shown a of the invention in that the vacuum-tubes further modification I 49 and 50 are connected in multiple. One seconda-ry winding 52 furnishes current for heating the filaments of the two tubes. This arrangement increases the current output of the set and also reduces the potential drop therein.

Fig. 6 shows a pair of two element vacuum tubes connected to rectify both halves of the wave. This is accomplished by dividing the secondary winding in two sections. One of the sections is connected to the tube 54 while the other is connected to the tube 55. In this way the alternations of the wave will be rectified upon the closure of the contacts of relay 16 for connecting the coil 52 in circuit with the cathode or heated filaments of tubes 54 and 55.

Although the invention has been illustrated and described as applied to a vacuum tube filled with an inert gas other types of rectifiers, such"as for example, a rectifier comprising a refractory cathode, such as a tungsten filament adapted to be heated to incandescence so as to emit electrons and a self-reconstructing anode of volatilizable material, such as mercury may be provided Without departing from the spirit and scope of the invention.

What is claimed is:

l. In a signal system, a line extending from a central office to a plurality of Waystations, means at each of the waystations selectively responsive to current impulses, a transformer at the cent-ral ofiice having a primary and a secondary Winding, a source of alternating current connected to the primary Winding of said transformer, ya rectifier having an anode and a cathode and associated with thc secondary winding of said transformer, a normally openelectrical connection for heating said cathode, and a transmitting mechanism having means for effecting the closure of said electrical connection for operating said rectifier and to impress signaling current impulses on said line.

2. In a signal system, a line extending from a central office to a plurality of waystations, means at each lof the way-stations selectively responsive to current impulses, a transformer having a primary and a pair of secondary windings, a source of alternating current connected to the primary winding of said transformer, a vacuum tube rectifier having an anode and a cathode, said anode being connected to one of said secondary windings, a normally open electrical connection extending from said cathode to the other of said secondary windings, and-a transmitting mechanism controlling the closure of said circuit connection for rendering said tube effective and for im ressingA signaling current impulses on said me.

3. In a signal system, a line extending from a central ofiice to a plurality of waystations, means at each of the way-stations selectively responsive tocurrent impulses, a transformer at the central ofiicc having a primary and a secondary winding, a source of alternating current connected to the primary Winding of said transformer, a rectifier having an anode and a cathode and associated with the secondary winding of said transformer, a normally open electrical connection for heating said cathode, a transmitting mechanism having means for effecting the closure of said electrical connection for operating said rectifier and to impress signaling current upon said line, and means controlled by said transmitting mechanism for intermittently reversing the polarity of the current impressed upon the line.

4. A signaling system comprising a line, a rectifier set having an anode and a cathode, a normally open electrical connection for said cathode, and an impulse transmitting mechanism associated with said line havino' means for controlling the closure of said connection whereby said rectifier set is rendered effective to supply Signaling current to said line.

5. A signaling system comprising a line circuit, a rectifier set having an anode and a cathode, a normally open electrical connection for said cathode, a transmitting mechanism having means for controlling the closure of said connection whereby said `rectifier set is rendered effective for supplying signaling current to said line circuit, and means controlled by said transmitting mechanism for intermittently reversing the polarity of Said signaling current.

6. In an electric control system, the combination with a controlling device, of a plurality of auxiliary devices to be controlled, electromagnetic means for controlling said auxiliary devices, means for operating said electromagnetic means comprising a source of alternating current, and a thermionic rectifying device, and means associated with said controlling device for rendering said rectifying device operative.

7. In a signaling system, a source of alternating current, a rectifying circuit coniprising a two element rectifier, a heating circuit for one of the elements of said rectifier, a plurality of signaling devices intermittently energized over a circuit from said alternating current source through said rectifier, said heating circuit being controlled by the means for intermittently energizing .said signaling devices.

In witness whereof, I hereunto subscribe my name this 20th day of November A. D.,

JOSEPH C. FIELD. 

